// MIT License
//
// Copyright (c) 2017 Advanced Micro Devices, Inc. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include <iostream>
#include <vector>
#include <algorithm>
#include <type_traits>

// Google Test
#include <gtest/gtest.h>
// HIP API
#include <hip/hip_runtime.h>
// rocPRIM API
#include <rocprim/rocprim.hpp>

#include "test_utils.hpp"

#define HIP_CHECK(error) ASSERT_EQ(static_cast<hipError_t>(error),hipSuccess)

template<class T>
struct times_two
{
    ROCPRIM_HOST_DEVICE
    T operator()(const T& value) const
    {
        return 2 * value;
    }
};

template<class T>
struct plus_ten
{
    ROCPRIM_HOST_DEVICE
    T operator()(const T& value) const
    {
        return value + 10;
    }
};

// Params for tests
template<
    class InputType,
    class UnaryFunction = times_two<InputType>,
    class ValueType = InputType
>
struct RocprimTransformIteratorParams
{
    using input_type = InputType;
    using value_type = ValueType;
    using unary_function = UnaryFunction;
};

template<class Params>
class RocprimTransformIteratorTests : public ::testing::Test
{
public:
    using input_type = typename Params::input_type;
    using value_type = typename Params::value_type;
    using unary_function = typename Params::unary_function;
    const bool debug_synchronous = false;
};

typedef ::testing::Types<
    RocprimTransformIteratorParams<int, plus_ten<long>>,
    RocprimTransformIteratorParams<unsigned int>,
    RocprimTransformIteratorParams<unsigned long>,
    RocprimTransformIteratorParams<float, plus_ten<double>, double>
> RocprimTransformIteratorTestsParams;

TYPED_TEST_CASE(RocprimTransformIteratorTests, RocprimTransformIteratorTestsParams);

TYPED_TEST(RocprimTransformIteratorTests, TransformReduce)
{
    using input_type = typename TestFixture::input_type;
    using value_type = typename TestFixture::value_type;
    using unary_function = typename TestFixture::unary_function;
    using iterator_type = typename rocprim::transform_iterator<
        input_type*, unary_function, value_type
    >;

    hipStream_t stream = 0; // default

    const size_t size = 1024;

    for (size_t seed_index = 0; seed_index < random_seeds_count + seed_size; seed_index++)
    {
        unsigned int seed_value = seed_index < random_seeds_count  ? rand() : seeds[seed_index - random_seeds_count];
        SCOPED_TRACE(testing::Message() << "with seed= " << seed_value); 

        // Generate data
        std::vector<input_type> input = test_utils::get_random_data<input_type>(size, 1, 200, seed_value);
        std::vector<value_type> output(1);

        input_type * d_input;
        value_type * d_output;
        HIP_CHECK(hipMalloc(&d_input, input.size() * sizeof(input_type)));
        HIP_CHECK(hipMalloc(&d_output, output.size() * sizeof(value_type)));
        HIP_CHECK(
            hipMemcpy(
                d_input, input.data(),
                input.size() * sizeof(input_type),
                hipMemcpyHostToDevice
            )
        );
        HIP_CHECK(hipDeviceSynchronize());

        auto reduce_op = rocprim::plus<value_type>();
        unary_function transform;

        // Calculate expected results on host
        iterator_type x(input.data(), transform);
        value_type expected = std::accumulate(x, x + size, value_type(0), reduce_op);

        auto d_iter = iterator_type(d_input, transform);
        // temp storage
        size_t temp_storage_size_bytes;
        // Get size of d_temp_storage
        HIP_CHECK(
            rocprim::reduce(
                nullptr,
                temp_storage_size_bytes,
                d_iter,
                d_output,
                value_type(0),
                input.size(),
                reduce_op,
                stream
            )
        );

        // temp_storage_size_bytes must be >0
        ASSERT_GT(temp_storage_size_bytes, 0);

        // allocate temporary storage
        void * d_temp_storage = nullptr;
        HIP_CHECK(hipMalloc(&d_temp_storage, temp_storage_size_bytes));
        HIP_CHECK(hipDeviceSynchronize());

        // Run
        HIP_CHECK(
            rocprim::reduce(
                d_temp_storage,
                temp_storage_size_bytes,
                d_iter,
                d_output,
                value_type(0),
                input.size(),
                reduce_op,
                stream,
                TestFixture::debug_synchronous
            )
        );
        HIP_CHECK(hipPeekAtLastError());
        HIP_CHECK(hipDeviceSynchronize());

        HIP_CHECK(
            hipMemcpy(
                output.data(), d_output,
                output.size() * sizeof(value_type),
                hipMemcpyDeviceToHost
            )
        );
        HIP_CHECK(hipDeviceSynchronize());

        // Check if output values are as expected
        if(std::is_integral<value_type>::value)
        {
            ASSERT_EQ(output[0], expected);
        }
        else if(std::is_floating_point<value_type>::value)
        {
            auto tolerance = std::max<value_type>(std::abs(0.1f * expected), value_type(0.01f));
            ASSERT_NEAR(output[0], expected, tolerance);
        }

        hipFree(d_input);
        hipFree(d_output);
        hipFree(d_temp_storage);
    }

}
